1. Field of Disclosure
The present disclosure of invention relates to an electrowetting display device and a driving method thereof.
2. Description of Related Technology
An electrowetting display device can be made to display a desired image by using a combination of a body of a polar liquid and a body of a non-polar liquid, where the two liquids are immiscible with each other. The electrowetting display device includes spaced apart upper and lower panels, a plurality of cells between the panels and divided from one another by interposed partition walls. Each cell includes a respective polar body of liquid and a non-polar body of liquid, both disposed in a space between the opposing panels. A pair of electrodes are provided in each cell for selectively applying electric fields that affect how the polar body of liquid and the non-polar body of liquid are disposed relative to one another and between the respective panels. A lyophobic layer is disposed on one of the electrodes of the cell. Since the lyophobic layer tends to push away from itself (repel) the polar liquid, the non-polar liquid tends to occupy the space between the repelled polar liquid and the repelling lyophobic layer.
When an appropriate electric field is applied in a region between the electrodes, the polar liquid may be urged by the electric field to move out of its normal position towards the surface of the otherwise repelling lyophobic layer and the non-polar liquid may swap position so as to gather in the place previously (and normally) occupied by the polar liquid. When this position swapping electric field is removed, the polar liquid is again repelled by the lyophobic layer and caused to move away from the surface of the lyophobic layer. In this case, the previously gathered non-polar liquid may return to its normal position to spread out along the surface of the lyophobic layer. The electrowetting display device uses the above-described phenomenon as well as an optical dyeing of the non-polar liquid in such a way that an area covered by the non-polar liquid containing the dye is selectively adjusted to thereby control the transmittance of light passing through the cell, thereby displaying a desired image.
Since the electrowetting display device does not use a polarizer for realizing its optical effects, it has a transmittance efficiency of light better than that of a liquid crystal display (LCD) which does use a polarizer for realizing its optical effects. However, the response time of the electrowetting display device to changing image signals is relatively large and thus it may be hard for the electrowetting display device to support fast moving (fast changing) images. In particular, it may take more time after gathering thereof, to again spread out the gathered non-polar liquid than to gather the non-polar liquid in the first place.
It is to be understood that this background of the technology section is intended to provide useful background for understanding the here disclosed technology and as such, the technology background section may include ideas, concepts or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to corresponding invention dates of subject matter disclosed herein.